Rotating electric sign device



Oct. 20, 1964 c. o. GLASGOW 3,153,292

ROTATING ELECTRIC SIGN DEVICE Filed May 14. 1962 2 Sheets-Sheet l /3 INVENTOR.

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United States Patent O 3,153,292 RQTATWG ELEllRlC SIGN DEVICE Clarence G. Glasgow, 2620 S. Yorktown, Tulsa, Okla. Filed May 14, 1962, Ser. No. 194,431 l Claims. (Cl. #l0- 39) The present invention relates to rotating electrical signs and the like, and more particularly, but not by Way of limitation, relates to a novel drive mechanism for rotating an electrical sign.

As is Well known to the average motorist, rotating electrical signs are extensively used by automobile service stations. These rotating signs generally comprise a large sign member having the outline of the shield or symbol of the particular oil company mounted atop a relatively tall post or pedestal. The sign members are rotated about a vertical axis by an electric motor which is connected through a reduction gear box to drive a shaft connected to the sign member. Some type of commutator rings are provided somewhere on the drive train for supplying electric power to illuminate the rotating sign member. In

most cases, the combination electric motor and reduction gear box is so large as to require a relatively large support pedestal in order to house the drive mechanism. Of course, this presents dificulties in designing an attractive pedestal, which is a very important consideration in advertising. But by far the greatest difficulty encountered in use of this type drive mechanism is created by Wind gusts striking the rotating sign member. The rotating sign member must be relatively large in order to be effective as an advertising device. Since the sign will invariably be positioned out-of-doors, the sign will be subjected to very high wind gusts, which in the southwestern regions of the country frequently reach 4G to 60 miles per hour. These gusts are by nature highly turbulent so that they invariably exert uneven forces on the ends of the rotating sign member, which produces sharp and severe jolts and backlashes to the gear train of the drive mechanism. Since the gear train is a positive mechanical drive, it is usually unable to absorb the severe shocks and strains and frequently the gears fail.

Therefore, it is an important object of the present invention to provide a drive mechanism for rota-ting an electrical sign which will absorb all shocks, jolts and baclilashes caused by wind forces and the like.

Another very important object of the present invention is to provide a highly compact drive mechanism for a rotating electrical sign which may be located in a relatively small tubular support pedestal.

till another object of this invention is to provide a highly novel exible torque coupling which may be economically manufactured and which may also be utilized as a commutator for supplying electrical power to the rotated sign.

Yet another object of the present invention is to provide a drive mechanism of the type described through which the electrical connection to the rotating sign can be very easily made.

A further object of the present invention is to provide a drive mechanism of the type described which may be easily installed to drive existing rotating signs.

A still further object of the present invention is to provide a drive mechanism of the type described which may be located either within the base or within the top of a support pedestal.

Another object of the present invention is to provide a drive mechanism of the type described which may be very easily serviced and which has an exceedingly long working life.

Still another object of the present invention is to provide a drive mechanism of the type described which has a rice highly simplified construction, a minimum of working parts and which can be economically manufactured, installed and operated.

Many additional objects and advantages will be evident to those skilled in the art from the following detailed description and drawings, wherein:

FIG. l is a side elevational View partly in section of a drive mechanism constructed in accordance with the present invention;

FIG. 2 is a cross sectional view taken substantially on lines 2-2 of FIG. l;

FIG. 3 is a schematic diagram of a rotating sign device constructed in accordance with the present invention;

FIG. 4 is an elevational View in section of the drive mechanism of FIG. l slightly modied for placement at the top of a pedestal;

FIG. 5 is a cross sectional view taken substantially on line 5 5, and,

FIG. 6 is a schematic view of another sign device constructed in accordance with the present invention.

Referring now -to the drawings, and more particularly to FIG. l, a compact drive mechanism constructed in accordance with the present invention is indicated generally by the reference numeral lil. The drive mechanism comprises a cylindrical housing l2 which may be fabricated from a short length of six or eight inch pipe. A ange ld is welded or otherwise connected to the bottom of the housing l2. A plurality of bolts 16 pass through apertures in the ange l. for connecting the device to a base plate 18, for example, when the drive apparatus is used in the sign construction illustrated in FIG. 3. However, those skilled in the art will realize that the housing l2 may be bolted to any suitable support frame as hereafter described in greater detail.

A rotary hydraulic motor 20 is connected by countersunk bolts 22 to a torque plate 24 which is secured Within the housing l2 by countersunk bolts 26. The rotary hydraulic motor 20 has an output shaft 28 which is vertically disposed along the axis of the cylindrical housing 12. The rotary hydraulic motor 2li is of conventional design and is commercially available. The hydraulic motor 26 has a maximum diameter of only a few inches so that it may be easily disposed within the cylindrical housing 12. The rotary hydraulic motor 2l) is preferably of the type employing only a rotary ring gear which revolves about a pinion which is attached to the output shaft 28. As the gear is rotated by hydraulic power fluid, the pinion is rotated at a reduced speed of approximately one-sixth :the rate of rotation of the ring gear. The hydraulic power iiuid is supplied to the hydraulic motor through a pair of tubular conduits 36 and 32 which may be fabricated from copper tubing or similar flexible conduit material. The conduits 3) and 32 may pass through a conveniently located aperture 3S in the cylindrical housing l2 and extend to a hydraulic fluid pump hereafter described.

The output shaft 28 of the rotary hydraulic motor 2i) is keyed to a flexible torque coupling, indicated generally by the reference numeral dil, which is a novel and very important feature of the present invention. Various details of construction of the flexible torque coupling 49 are shown in FIGS. l, 2, 4 and 5, as will presently be described. The torque coupling 4t) comprises a mass of butyl rubber 42 which is sandwiched between and bonded to upper and lower coupling plates ld and 46 respectively. A plurality of perforated plates 48, 50 and 52 are disposed in parallel relationship at right angles to the axis of rotation of the coupling and are molded in the interior of the rubber mass 42. The upper yand lower coupling plates 44 and 46 are bonded to the rubber mass 42 by any suitable means, but preferably are bonded to the mass during the molding of the coupling 40, in which case the coupling plates 44 and 46 serve as the ends of the casting mold. The surfaces of the coupling plates 44 and 46 are preferably provided with annular grooves 54 and 56 and radially extending bores 58 and 6d, as best seen in FIGS. 1 and 5. Similarly, the several plates 48, 51B and 52 are provided with a plurality of apertures 62, as typically illustrated in the plate 52 in FIG. 2. An axial bore 64 is provided along the axis of the torque coupling 4t) and extends through the upper coupling plate 44, the mass of butyl rubber 42 and the three perforated plates 48, 54B and 52. Another axial bore (not referenced) extends partially through the lower coupling plate 46 for receiving the drive shaft 28 of the rotary hydraulic motor 2t). A pair of keys 66 provide a positive couple between the drive shaft 28 and the lower coupling plate 46.

it will be noted that the outer circumferential edges of the three plates 48, 56 and 52 extend slightly beyond the periphery of the body of butyl rubber 42 so as to provide electrical slip rings or commutator rings for purposes to be hereafter described in greater detail. it will also be noted that the plates 48, 50 and 52 extend inwardly to the bore 64 so as to provide electrical conductors from the exterior surface through the mass of butyl rubber 42 to the axial bore 64. In this connection, it will also be noted that the plates 48, Sil and 52 are electrically insulated one from the other and from all other conductive material by the body of buty rubber 42.

It will be obvious to those skilled in the art that the flexible torque coupling 4d may be very easily fabricated. For example, the upper and lower coupling plates 44 and 46 and the perforated plates 43, Sti and 52 may be cast or machined in any suitable manner. Then the coupling plates 44 and 46 may be used to form the ends of a mold while the perforated plates 48, 50 and 52 are held in spaced parallel relationship within the mold. Butyl rubber 42 may then be injected into the moid through the axial bore 64 and will easily pass between the five plates and will penetrate the annular grooves 54 and 56 and the radial bores 53 and 6i) of the coupling plates 44 and 46, respectively, to insure an integral bond having as much strength as the butyl rubber itself. The radial bores 58 and 6d, in addition to assuring a maximum strength bond, permit gases to escape and also provide an indication of when the mold is completely lled with rubber to assure a top quality product. Similarly, the butyl rubber will be injected into the large plurality of apertures 62 in the commutator plates 48, 51) and 52 to provide an integral mass of butyl rubber and assure positive bonding to the three commutator plates which also serve to stifen and strengthen the torque coupling 4t) as hereafter described.

Electrical brushes 70, '72 and 74 are held in sliding contact with the outer peripheries of the plates 4S, Sil and 52, respectively, by brush-holder arms 76, 78 and titi, respectively. The brushes are received in counterbores (not referenced) in the respective arms. Conductors S2, S4 and S6 are electrically connected to the brushes and pass through bores in the brush-holder arms. The three conductors may then be conveniently bound together by electrical tape and as a collective lead d'7 passed through an aperture 88 in torque plate 24 and extended along the path of the hydraulic huid conduits 319 and 32 to a source of electrical power. The brush-holder arms '76, l and 8d are pivotally supported on a vertically disposed stud 9d which may be conveniently threaded into the torque plate 24. The brush-holder arms 76, '78 and Si) may conveniently be fabricated from wood and may be held in spaced relationship by suitable bushings 912, 94 and 96 which are disposed around the stud 91). A nut $7 may be threaded onto the upper end of the stud dit to complete the assembly. A second stud 93 is also threaded into the torque plate 24 and, as best seen in FIGS. 2 and 5, is provided with a longitudinally extending groove 11111. A coil spring such as indicated by reference numeral 102 is connected to each ofthe brush-holder arms and is received in the longitudinal groove 101B to continually exert a bias urging the respective brush-holder arms toward the flexible torque `coupling 40 so as to firmly press the several brushes against the outer circumference of the plates 48, 50 and 52 to insure continuous electrical contact as the torque coupling 46 rotates.

An adapter 1114 which is comprised of a plate portion 146 and a shank portion 108 is connected to the upper coupling plate 44 by countersunk bolts 110. The adapter 1114 is provided with an axial bore 112 which registers with the bore 64 and preferably is of the same diameter. A tubular drive shaft 114 is telescoped over the shank portion 148 and is connected thereto by a shear pin 116 which may be retained in place by Wedging or any other suitable method. The drive shaft 114 extends upwardly through a hollow pedestal and is connected to rotate a sign member as hereafter described in greater detail in connection with FIG. 3.

A thrust bearing indicated generally by the reference numeral 129 is provided to support the load imposed on the drive mechanism. The thrust bearing is comprised of an outer race 122, an inner race 124 and a plurality of tapered roller bearings 126 which are spaced by a conventional spacer ring (not illustrated). The thrust bearing is received within a counterbore in the upper end ofthe cylinderical housing 12 and the outer bearing race 122 rests on an annular shoulder 127 formed by a counterbore 128. The outer bearing race 122 is preferably press-fitted within the counterbore so as to prevent rotation and subsequent loosening of the bearing race. rthe inner bearing race 124 may be presstted around the upper coupling plate 44 and abut against the plate portion 1116 of the adapter 1114, so that the thrust bearing 12? will support any vertical load imposed on the bearing by the drive shaft 114.

A cylindrical plug insert 13d fabricated from wood, plastic or any other similar nonconductive material is disposed in the bores 64 and 112. Three bowed leaf springs 132, 134 and 136, as best seen in FIG. 1, are connected to the plug insert 130. The springs 132, 134 and 136 are fabricated from a conductive material and are axially spaced along the plug insert to contact the innermost edge of the ring plates 48, 50 and 52, respectively. The springs 132, 134 and 136 are also circumferentially spaced around the plug insert so that three grooves 141B, 142 and 144 may be provided in the plug insert 130 to receive three conductors indicated collectively by the reference numeral 146 in FIG. 1. The lower ends of the conductors 146 are electrically connected to the three springs 132, 134 and 136. The conductors are insulated by a conventional insulating sheath 148, and extend upwardly through the drive shaft 114 to the electrical sign driven by the shaft as hereafter described. It will be noted that plug insert 1319 rests on the upper surface of the bottom coupling plate 46 and, as best seen in FIG. 4, is suficiently short as to permit the shear pin 116 to be inserted through the drive shaft 114 and the shank portion 1113 of theV adapter 104. However, the plug insert 13@ preferably has a tab portion 150 which extends beside the shear pin 116 to a point above the upper end of the shank portion 108 so that the plug insert 130 may conveniently be removed from the bores 112 and 64.

A typical sign installation in accordance with the present invention is indicated generally by the reference numeral 1611 and is shown in the schematic diagram of FIG. 3. A source of hydraulic power fluid indicated generally by the reference numeral 161 is comprised of a hydraulic pump 162, driven by a suitable electric motor 164, which withdraws hydraulic fluid from a reservoir 166 through a strainer 16S. The hydraulic pump forces the hydraulic fluid through the conduit 30 to the hydraulic motor 2t) of the drive mechanism 10. The reservoir 166, the hydraulic pump 162 and the electric motor 164 may conveniently be located within the service station in the general area of the air compressor, for example. The drive mechanism is positioned within a tapered pedestal 170 and is supported on the base plate 18, which is connected to a suitable foundation. A sign member 172 is rotatably supported atop the pedestal 170 by a suitable bearing 174. The tubular drive shaft 114 extends vertically upwardly from the drive mechanism 10 and is connected to the rotating sign 172. The electrical conduits 148 extend through the tubular drive shaft 114 to the interior of the sign member 172. Used hydraulic huid from the drive mechanism 10 is returned through the flexible conduit 32 to the reservoir 166.

Another rotating sign device is indicated generally by the reference numeral 180 and is illustrated schematically in FIG. 6, and in greater detail in FIG. 4. The same source of hydraulic power fluid 161 is utilized in combination with the sign device 180 including the hydraulic pump 162, which is driven by the electric motor 164, and

`the hydraulic fluid reservoir 166. Hydraulic fluid is also supplied through the flexible conduit 30 and is returned through the flexible conduit 32 to the reservoir 166. The sign device 180 has a tubular pedestal 182 which may conveniently be formed from a joint of six or eight inch pipe supported by a concrete base 184. The drive mechanism 10 is slightly modified as hereafter described and accordingly is designated by the reference numeral 10a. The modified drive mechanism 10a is positioned atop the pedestal 182 and rotatably supports a sign 186. The fluid conduits and electrical power leads extend upwardly through the pedestal 182 to the drive mechanism 10a.

Referring now to FIG. 4, the modified drive mechanism V10a is essentially the same as the drive mechanism 10 `illustrated in FIG. 1. Accordingly, all parts of the drive mechanism 10a which are identical in construction to the parts of the drive mechanism 10 are indicated by the same reference numerals. tween the drive mechanism 10a and the drive mechanism 10 is that the housing 12a is provided with an extension 188 within which a shoulder 190 is formed by a counterbore for supporting a second thrust bearing 192. The thrust bearing 192 may be substantially similar to the thrust bearing 120 and comprises an outer race 194 which is supported by the shoulder 190, an inner race 196, and a plurality of tapered roller bearings 198.

A short drive shaft 200 is connected to the sign member 186 and is telescoped over the shank portion 108 of the adapter 104. The shear pin 116 passes through the tubular drive shaft 200 and through the shank portion 108 to couple the adapter 104 to the shaft 200 as previously described in connection with the drive mechanism 10. A load bearing flange 202 interconnects the drive shaft 200 and the sign member 186 and has a shank portion 204 around which the inner bearing ring 196 is press-fitted. The connecting flange 202 may also be provided with a peripheral depending .skirt 206 which extends downwardly around the upper end of the housing 12a to provide a substantially water-tight joint. Those skilled in the art will appreciate that the thrust bearings 120 and 192 or an equivalent bearing structure will adequately support the rotating sign member 186 and will effectively withstand wind loads which may strike the large area of the sign member and tend to topple the sign from the pedestal.

From the above detailed description, it will be apparent that several highly useful embodiments of the present invention have been disclosed. The basic drive mechanism 10 illustrated in FIG. l may be utilized in combination with almost all presently existing rotating sign assemblies. The source of hydraulic power fluid 161 may be located within the service station building so as to be conveniently serviced and continually protected from the weather. The rotary hydraulic motor provides a very compact and simplified source of high torque to rotate the sign member. The hydraulic motor 20 is lubricated by the hydraulic uid and requires no servicing so that it may be somewhat permanently installed in relatively inaccessible locations with a sign supporting ped- The primary difference beestal. The rotary hydraulic motor 20 functions as a fluid 'shock absorber because any wind loads transmitted through the drive train to the hydraulic motor will tend to 4be absorbed by the hydraulic drive fluid. Further, the hydraulic motor 20 serves as a compact, continuously lubricated reducing gear box to slowly turn the sign member at approximately six r.p.m. while delivering maximum torque.

The novel flexible torque coupling 40 will absorb most all gust wind loads transmitted through the drive shaft 114. It is an important feature, although not a limiting one, of the present invention that the mass 42 be fabricated from butyl rubber which has an exceedingly great capacity to absorb shock without producing rebound. The novel configuration of the upper and lower coupling plates 44 and 46 insures that the mass of butyl rubber 42 will be securely bonded to the respective coupling plates so as to adequately transmit the torque from the hydraulic motor 20 to the drive shafts. The perforated plates 48, 5l) and 52 strengthen the body of butyl rubber 42 and thereby increase its maximum torque rating. The perforated plates 4S, S0 and S2 also serve as commutator rings for providing electrical power to the rotating sign member 172 and 186. This results in a very compact, well insulated structure which may be very economically manufactured which has a dual function. The plug insert provides a very convenient means for electrically connecting the leads 146 and the respective commutator rings. Three commutator rings are illustrated so that the conventional power leads for alternating current, together with a ground wire, may be utilized for maximum safety. Because of its very compact size, the drive mechanism 10a may be wholly housed within a relatively small diameter pole 182 which may be used to support the rotating sign member 186 which results in a very simple and attractive advertising device. Further, locating the drive mechanism 10a at the top of the tubular pedestal 182 facilitates assembly of the sign device 180. For example, the drive mechanism 10a may be connected to the sign 186 before the two are placed atop the pole or pedestal 182, and then the sign member and drive mechanism hoisted to the top of the pedestal and the bolts 212 installed to attach the rotating sign in position. Since the drive mechanism 10a requires virtually no servicing during its life, the location of the drive mechanism atop the pole is highly practical. If desired, the housing 12a may be made integral with the pedestal 182 and the interior working parts of the drive mechanism 10a lowered into position as the sign member 186 is placed atop the housing 12a.

Although several preferred embodiments of the present invention have been described in detail, it is to be understood that various changes, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

What is claimed is:

1. A rotating sign device comprising, in combination:

a sign support pedestal;

an electrical sign rotatably supported by the pedestal;

a motor support means;

a rotary hydraulic motor having a rotating output shaft supported by the support means;

a hydraulic power iluid source connected to the motor for supplying hydraulic fluid under pressure to operate the motor;

a drive shaft connected to rotate the sign;

flexible torque coupling means interconnecting the drive shaft and the output shaft, the flexible torque coupling means being fabricated from a resilient electrically nonconductive material,

a plurality of electrically conductive slip rings on the flexible torque coupling, the slip rings being electrically insulated one from the other by the resilient electrically nonconductive material;

brush means for making sliding electrical contact with each of the slip rings;

electrical circuit means connected to the brush means for supplying electrical power to the brush means; and

electrical circuit means interconnecting the slip rings and the electrical sign.

2. A drive mechanism for rotating an electrical sign rotatably supported by a pedestal comprising:

a tubular drive shaft connected to the sign;

a rotary motor having an output shaft;

a flexible torque coupling interconnecting the output shaft and the drive shaft, the flexible torque coupling being fabricated from a resilient, electrically nonconductive material;

a plurality of electrical slip rings on the iiexible torque coupling;

an electrical brush means in sliding contact with each of the slip rings;

first electrical circuit means connected to the brush means for supplying electrical power thereto; and

second electrical circuit means interconnecting the slip rings and the electric sign, the second circuit means extending through the tubular drive shaft.

3. A drive mechanism for rotating an electrical sign rotatably supported by a pedestal, the drive comprising:

a tubular drive shaft connected to the sign for rotating the sign;

a rotary motor having an output shaft;

a flexible torque coupling interconnecting the output shaft and the drive shaft;

the flexible torque coupling comprising a mass of resilient electrically nonconductive material, a coupling plate bonded to opposite ends of the mass for connection to the output shaft and to the drive shaft, respectively, and a plurality of electrically conductive discs disposedin spaced parallel relationship within the mass, each of the discs being generally perpendicular to the axis of rotation of the mass and having a circularly shaped outer periphery, the axis of which is aligned with the axis of rotation of the mass;

electrical brush means in sliding contact with the periphery of each of the discs;

rst electrical circuit means connected to the brush means for supplying electrical power to the brush means;

second electrical circuit means connected to the discs and extending through the tubular drive shaft for supplying the electrical power to the sign.

4. A flexible torque coupling for interconnecting the drive shaft of a drive motor and an electrical apparatus to be rotated, the torque coupling comprising:

a mass of electrically nonconductive resilient material having opposite ends;

iirst and second coupling means connected to each end of the mass for connecting the mass to the drive shaft of the drive motor and to the electrical apparatus to be rotated, respectively, such that the mass will be rotated about an axis of rotation; and

a plurality of electrically conductive slip members connected to the mass, the slip members being electrically insulated one from the other and having a circularly shaped periphery, the center of which coincides with the axis of rotation of the mass.

5. A flexible torque coupling for interconnecting the drive shaft of a motor and an electrical apparatus to be rotated, the torque coupling comprising:

a mass of electrically nonconductive resilient material having opposite ends; i

iirst and second coupling plates bonded to the ends of the mass for connecting the coupling in a drive train such that .the mass will be rotated about an axis of rotation;

a plurality of electrically conductive circular plates i S embedded in the mass of resilient material, the circular plates being disposed in spaced relationship at right angles to the axis of rotation of the mass with the peripheries ofthe plates exposed;

a bore extending at least partially through the coupling in the longitudinal direction; and

electrical circuit means extending through the bore and connected to the circular plates.

6. A flexible torque coupling for interconnecting the drive shaft of a motor and an electrical apparatus to be rotated as defined in claim 5 wherein:

the mass of electrically nonconductive resilient mate- -rial is butyl rubber.

7. A drive mechanism for rotating an electrical sign rotatably supported by a pedestal, the drive comprising:

a vertically disposed tubular housing;

a thrust plate connected within the tubular housing at a midpoint thereof, the thrust plate having a central aperture;

a rotary hydraulic motor connected to the thrust plate, the hydraulic motor having a rotary output shaft extending through the aperture to a point above the thrust plate;

a source of hydraulic power iluid connected to the motor for operating the motor;

a flexible torque coupling comprising a mass of resilient, nonconductive material having opposite ends, and first and second coupling plates bonded to the opposite ends, the iirst coupling plate being connected to the output shaft of the motor for rotation of the mass about an axis of rotation generally perpendicular to the coupling plates, a plurality of electrically conductive circular discs embedded in the mass, `the discs being spaced apart and disposed at substantially right angles to the axis of rotation with the peripheries of the discs exposed, and a bore extending axially through the mass and through the discs;

electrical `brush means supported by the thrust plate in sliding contact with the periphery of each of the discs; and

electrical circuit means extending through the bore an-d electrically connected to each of the discs.

8. A drive mechanism for rotating an electrical sign rotatably supported by a pedestal as defined in claim 7 wherein:

the electrical circuit means extending through the bore is comprised of a nonconductive elongated member disposed in the bore, an electrical contact connected to the member for each of the discs of the torque coupling, the contacts being longitudinally spaced along the member such that each of the contacts will simultaneously engage one of the discs and establish an electrical circuit, and an electrical conductor connected to each of the contacts and extending upwardly through the bore for connection to a drive shaft of a rotated `sign member.

9. A rotating sign device comprising:

a vertically disposed tubular pedestal;

a thrust plate connected within the tubular housing at a point adjacent the upper end thereof;

a rotary hydraulic motor connected to the thrust plate, vthe motor having an output shaft extending above the thrust plate;

a source of hydraulic power iiuid connected to the motor for operating the motor;

a flexible torque coupling comprising a mass of resilient, nonconductive material having opposite ends and rst and second coupling plates bonded to the opposite ends, the first coupling plate being con- 4 nected to the output shaft of the motor for rotation of the mass about an axis of rotation generally perpendicular to the coupling plates, a plurality of electrically conductive circular discs embedded in the mass, the discs being spaced apart and disposed at substantially right augies to the axis of rotation with the peripheries of the discs exposed, and a hore extending axially through the second coupling plate, through the mass and through at least all but one of the discs;

electrical brush means supported by the thrust plate in sliding contact with the periphery of each of the conductive discs;

a tubular drive shaft connected to the second coupling plate and extending vertically upwardly through the pedestal;

a sign member connected to the `tubular drive shaft and rotatably supported atop the pedestal;

electrical circuit means connected to the brush means for supplying electrical power thereto; and

electrical circuit means connected to each of the discs and extending through the bore in the iexible torque coupling and through the tubular drive shaft to the sign member.

10. A drive mechanism for rotating an electrical sign `supported in vertically spaced relation to the ground comprising:

a drive shaft connected to the sign;

a motor having an output shaft;

a iiexible torque coupling of resilient, electrically nonconductive material drivingly connecting said output shaft with said drive shaft;

electrical slip ring means on the flexible torque coupling;

electrical brush means in sliding contact with said electrical slip ring means;

first electrical circuit means connected to the brush means for supplying electrical power thereto; and

second electrical circuit means interconnecting said slip ring means and said electric sign.

References Cited in the le of this patent UNITED STATES PATENTS 1,754,258 Broadwell Apr. 15, V1930 2,129,595 Varkonda Sept. 6, 1938 2,396,848 Haushalter Mar. 19, 1946 2,741,861 Roe Apr. 17, 1956 2,996,900 Fermier Aug. 22, 1961 3,004,358 Clark Oct. 17, 1961 

4. A FLEXIBLE TORQUE COUPLING FOR INTERCONNECTING THE DRIVE SHAFT OF A DRIVE MOTOR AND AN ELECTRICAL APPARATUS TO BE ROTATED, THE TORQUE COUPLING COMPRISING: A MASS OF ELECTRICALLY NONCONDUCTIVE RESILIENT MATERIAL HAVING OPPOSITE ENDS; FIRST AND SECOND COUPLING MEANS CONNECTED TO EACH END OF THE MASS FOR CONNECTING THE MASS TO THE DRIVE SHAFT OF THE DRIVE MOTOR AND TO THE ELECTRICAL APPARATUS TO BE ROTATED, RESPECTIVELY, SUCH THAT THE MASS WILL BE ROTATED ABOUT AN AXIS OF ROTATION; AND A PLURALITY OF ELECTRICALLY CONDUCTIVE SLIP MEMBERS CONNECTED TO THE MASS, THE SLIP MEMBERS BEING ELECTRICALLY INSULATED ONE FROM THE OTHER AND HAVING A CIRCULARLY SHAPED PERIPHERY, THE CENTER OF WHICH COINCIDES WITH THE AXIS OF ROTATION OF THE MASS. 